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This report was compiled by an ADRC visiting researcher (VR) from ADRC
member countries.
The views expressed in the report do not necessarily reflect the views ofthe ADRC. The boundaries and names shown and the designations usedon the maps in the report also do not imply official endorsement or
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A PRELIMINARY STUDY OF THE DROUGHTMITIGATION PRACTICES OF AGRICULTURE SECTOR IN JAPANAND LOOKING FOR POSSIBILITIES TO APPLY BEST PRACTICES TO SRI LANKA

Research Reportfor the Visiting Researcher Program (2011 A)
Asian Disaster Reduction CentreKobe,, Japanp
W.M.S.B.WANNINAYAKE
Assistant Director (For Kurunegala District)
Disaster Management Centre,
Ministry of Disaster Management, Sri Lanka

2011 August 29

Background of the Research
What is Drought
Drought can be simply defined as a situation where•Drought
human demand for water exceeds the available supply.
•Droughts result from a combination of meteorological,
meteorologicalphysical and human factors.
•FourFtypes
toff Droughts
Dht
1. Meteorological drought ‐ Lack of precipitation from normal ,oversome period of time
2. Hydrological drought ‐ Deficiencies in surface and subsurface watersupplies3. Agricultural drought – Lack of needed soil moisture of a particular
crop at a particular time
4 Socio4.
Socio‐economic
economic drought – Associating with supply of and demand foran economic good.

Objective of the Research
To study the Japanese drought mitigation practices
and identify the best practices which can be appliedin Sri Lanka.

Significance of the Research
As a country mainly based on agriculture the Sri
Lanka has to take the possible maximum production inagriculture, for that, should minimize the losses bydroughts to keep the development targets,targets specially ineconomy.
Therefore it needs to find solutions to mitigate
droughts’ effects in agriculture.
This research is done to study the Japanese methods
for drought mitigation.
Methodology
Data Collection

Data collection was mainly done from websites.
 Some places where drought mitigation practices
are going on, were visited and got some information.


Data Analysis

Analyzed data in previous studies were mostly used.
used Descriptive method had to be applied, rather thanany statistical or mathematical analyzing tools due tovery limited period of time to complete the research.
Study Area

Agriculturalgareas, in Japanp and in Sri Lanka, wheredroughts are occurred in time to time
Limitation of the Study

Within a two weeks period of time I have tocomplete the research.
 Therefore only few research techniques wereable to apply in the study.
Droughts in Japan ‐ 1
Though Japan receives abundant precipitation, water
shortages are frequentfrequent.
Due to marked topographic differences, small rivercatchments and sudden drops in altitude,altitude droughts arecreated.
3
Total annual water use is approximately 85.2 billion m .
88 % of which is obtained from rivers. The agriculture
sector uses more thanh 65 % off annuall water abstraction
bwhile domestic – 20% and industrial – 15%Droughts in Japan ‐ 2
Long‐term trend of temperature change in Japan ‐Average annual surface air temperature has increased byapproximately 1oC over the past 100 years.
 Years of low rainfall have become frequent since around1970.
 Amount of precipitation was much below average in
1973, 1978, 1984, 1994, and 1996, and water shortages
caused damage.
1994 water shortage covered almost all Japan.
Approximately 16 million people were affected at least
once bybsuspended
d d or reduced
d d watert supply.
lAgricultural production losses ‐ 140 billion yen.
Experiences of Water Shortage
from 1991 to 2010
(10 Prefectures of 05 regions)<Kanto Koshin region>
B10: Gunma Prefecture
B11: Saitama PrefectureNo
1 year2-3 years
4-7 years
more than 8 years

B10
B11
B8
B9
B7
A1

B5

B3

B2

A2

B6

B1

B4

<Shikoku region>
A1: Kagawa Prefecture
A2: Chuyo area, Ehime Prefecture
B1 CentralB1:C t l area, Kochi
K hi Prefecture
P f t<Tokai region>
B8: West area, Aichi Prefecture
B9: East area, Aichi Prefecture<Kinki region>
B6: North area, Wakayama Prefecture
B7: North area, Nara Prefecture<Kyushu region>
B2: Central area, Fukuoka Prefecture
B3: Kitakyushu area, Fukuoka Prefecture
B4: Fukuoka area,area Fukuoka Prefecture
B5: North area, Nagasaki Prefecture

Source: Ministry of Land, Infrastructure, Transport, and Tourism “Water Resource in Japan in FY2011” (August 2011) p.267

River systems and rivers affected by droughts in the year 2005Source: Atsushi Kobayashi, River Bureau, Ministry of Land, Infrastructure, Transport, and Tourism,
www.mlit.go.jp/river/trash_box/paper/pdf_english/36.pdf (Accessed on 2011/8/15)

Drought Management Measures in Japan
Policyy makingg (Acts, Plans) Devolution power (Central, Prefectural,Municipal Community)
Municipal,
 Dam constructions to distribute water tovulnerable areas
 Community organization (Drought Conciliation
Council ) Using super technology
 Other methodsCommunity Response to Droughts
Water users first try voluntarily to adjust their wateruses. They save water by means ofWater
Water‐sharing
sharing (method of distributing water inaccordance with designated times and turns)
 Intensification of repeated use
 Supplementary irrigation from undergroundwater or water from ponds Irrigation
I i ti byb rotation
t ti

1.Irrigation by Rotation
Water management practices for watersaving are as follows;(1) Irrigated area is divided into smaller
units and each unit receives water inturn(2) Each field receives water by priority
and with specified duration(3) Water
W t isi withdrawn
ithdfromftheth sourcesby the interval of several days.

3. Supplementary
Irrigation
4.Sacrificed Field
Due to the shortage of thevolume of water, management
practices such as theintensification of rotational supply
and reuse do not work effectively.
Under such conditions, watersupply is cut off to some parts of
paddy to save
Other parts.

2. Reuse of Water
Upstream drainage
water is dammed up andreuse for irrigation
Purposepwith ppumps.
p

When water shortage persists
even after the rotational
supply or reuse,
supplementary water sources
are utilized Such as under‐
ground water by diggingtemporary wells, dead waterof ponds and reservoirs which
are not normally
Implemented,
ld or watertransferred from other uses.

Source: Ministry of Agriculture, Forestry and Fisheries “Irrigation Water Use in Agriculture in Japan” pp.11‐12

Drought Conciliation Council for Water Use Coordination
By the River Law, the provisions have beenmadeDrought Conciliation Council's,composed of the river administrator,water users,, local government,g, and otherconcerned agencies, have been
established in a lot of river basins.
This council has contributed to water useconciliation during droughts as a forum
for mutual consultation amongstakeholders.
k h ld River administrators may makenecessaryy intermediation or arbitration incase no agreement is reached in theconsultation among water users.
Government
Government’ss intervention is the secondmeasurement.

Drought water‐use conciliation councils established (as of March 2002)
Types of River
SystemNo. of EstablishedRiver Systems

No. of Established
Organizations

Class A69103

Class B

25

25

Source: Ministry of Land, Infrastructure, Transport, and Tourism “Rivers in Japan” (September 2006) p.52

Dam Constructions & Drought Mitigation in Japan

Source: Atsushi Kobayashi, River Bureau, Ministry of Land, Infrastructure, Transport, and Tourism,
www.mlit.go.jp/river/trash_box/paper/pdf_english/36.pdf (Accessed on 2011/8/15)

Sameura Dam
Having faced to the drought conditionin 2004, Japanese government decided
to build the Sameura Dam in Yoshino
River in Shikoku region as solution tocontrol the future impacts.
Yoshino river basin is a one of thebiggest river basin in Japan including acatchment
harea off 3750 kmk 2
 Length of the river is 194 km and 20%of the land area of Shikoku islandincl ded to the Yoshino River
includedRi er basin
Both the floods and droughts areexperience in this basin
The major construction of this project
was the Sameura Dam which was builtwith four purposes that are as, flood
control in Yoshino River,River maintenance ofnormal function the river water, watersupply to Shikoku four prefectures forirrigation and power generation
Yoshino river system

Donto Dam
Donto dam in Kako Riversystem in Miki City area, hasbeen constructed under theToban‐Yosui Irrigation Project.
 The objectives of the project
are toIrrigation watersupplying to the paddy fields
andd tap
t watert supplying
l i tot thethurban areas. For four cities andone town in Hyogo prefecture Ancient water diversion works
under the Donto dam at Inamiplateau
 Ponds have been constructedto supply water to paddy lands
at Inami plateau
Ichikawa River System andDrought Management
Name of Dam(Year)

Managed byPurpose

Capacity(Effective)

Kurokawa
Dam(1974)

KansaiElectric PowerCo. Inc.

Industrial Use,
Irrigation, TapWater, andPower
Generation

21.36 million
m3Ik
Ikuno
DamD(1972)H
Hyogo
Prefecture

Flood
Fl
dC
Control,t lIndustrial Use,Irrigation andTap Water

17 0 million
17.0illim3

Hase Dam &Ota Dam(1995)

KansaiElectric PowerCo Inc.
Co.
IncPower
Generation

8.26 million
m3 and 8.66
million m3

Kotani Dam(2001)

Hyogo
Prefecture

Tap Water andIrrigation

16.1 millionm3

Ota dam

Kurokawa Dam
Hase Dam

Ikuno Dam

Kotani dam

Source: Himeji Public Works Office, Hyogo Prefectural Government

Effects of dams in drought condition

Source: Atsushi Kobayashi, River Bureau, Ministry of Land, Infrastructure, Transport, and Tourism,
www.mlit.go.jp/river/trash_box/paper/pdf_english/36.pdf (Accessed on 2011/8/15)

Droughts in Sri LankaGeography•SriS i LLankak iis an IIslandl d•Location
I di ocean, IIndian
Indiandi subb
continent
Latitudes 50.55
55’‐990.55
55 N
Longitudes 790.42’‐810.52’ E
Land area : 65,610
65 610 km2•Land•Maximum Length
g : 445 km•Maximum Breadth : 225 km

Climate• Due to the location of Sri Lanka, the climate could becharacterized as tropical.
• Sri Lanka lies on Inter Tropical Convergent Zone (ITCZ).
• TheTh ttopographicalhi l ffeatureststrongly
tl affect
ff t ththe spatial
ti lpatterns of winds, seasonal rainfall, temperature,relati e hrelative
humidity
midit and other climatic
limati elements,
elements
particularly during the monsoon season.
• Rainfall in Sri Lanka has multiple origins. Monsoonal,Convectional and expressional• The mean annual rainfall varies from 900mm to5000mm.

•The
Th mean annuall ttemperaturetvaries
i ffrom16
160c to27
t 270c.
•Climate experienced during 12 months period in SriLanka can be characterized in to 4 climate seasonspFirst Inter‐monsoon Season – March‐April
Southwest monsoon season – May‐September
Second Inter‐monsoon
Inter monsoon season – October‐NovemberOctober November
Northeast Monsoon season ‐ December – February•Three Agro ecological zones based on climaticconditions.
•Wet zone
Inter mediate zone
•Inter•Dry zone

Agro‐ecological Zone Map of Sri Lanka

Droughts in Sri Lanka
Low rainfall during monsoons is
the cause for droughts in south‐
eastern, north‐central and north‐western areas of Sri Lanka
Drought of serious nature occur
once ini aboutb
3‐43 years
Severe drought of nationallysignificant in about 10 years also
impacting hydro‐power
generation
Major droughts havepduringg the years
yexperienced
1935‐37, 1947‐49, 1953‐56,1974‐77, 1981‐83, 1993‐94,
2000‐01 andd 2003‐04 (DMC(2005)
Drought affected areas in Sri Lanka, 1974 ‐ 2007

Impact of Droughts in Sri Lanka

Trend Line of occurrence of Droughts
g in Sri Lanka

Drought Mitigation Measures in Sri Lanka
Construction of large reservoirs andsmall tanks to store water

Irrigation systems of ancient
Sri Lanka consist of a large
number of village tanks,gigantic reservoirs and a
intrinsic network of waterchannels
hl connecting
i thesehtanks while supplying water tofarming land.
landThere are about 30,000 tanks
in Sri Lanka
anka of which themajority was built form 3rdcentury BC to 12th century.
Names of some large reservoirs
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

Badagiriya Wewa ‐ Pallemalala
Basawak Kulama ( Abaya ) Tank
Bathalagoda Tank ‐Debera Wewa ‐ Tissamaharamaya
Girithale Tank
Mahagala Wewa ‐ Hambantota
Minneriya Tankk
Nachchaduwa Reservoir ‐ Anuradhapura
Nuwara Wewa ‐ Anuradhapura
Nuwara Wewa ( Kandy Lake ) ‐ Kandy
Panda Wewa ‐ Panduwasnuwara
Parakrama Samudraya ( Ocean of Parakrama) ‐Pollonnaruwa
Siyambalagamuwa Reservoir
Sorabora Weva ‐ Mahiyangana
Thabbowa Tank ‐ Puttalama
Thuruwila Irregation Tank ‐ Anuradhapura
Tissa Wewa ‐ Anuradhapura
Tissa Wewa ‐ Tissamaharamaya
Vavunikulama Reservoir ‐ Vavunia
Weerawila Wewa ‐ Wellawaya
Yoda Wewa ‐ Mannar DistrictYoda Wewa ‐ Tissamaharamaya

Distribution of large reservoirs and small tanks

Renovation of small tank cascades for Drought Mitigation
Village Tank Cascade System

Application of Japanese methods in Sri Lanka









Policies making (Acts,Plans)l )Devolution power (Central,Provincial,, Local))Large reservoirs & smalltanks constructions to store
water for drought season
Community organization(Farmer organizations)
Lack of capital &technology
Other methods (deep wells,wells
tube wells, drip irrigation,
new varieties of crops)





Policy making (Acts, Plans)
Devolution power (Central,Prefectural, Municipal,CCommunity)it )Dam constructions to
distribute water to vulnerable
areas
Community organization(Drought Conciliation Council )Usingg superp technology
gy
Other methods